C2S VPN dropping over wireless but works over direct cable

Hello,

I have a issue with keeping VPN session over the Wirelless but is stable over cable.

I’m connecting from my laptop using client-to-site VPN to corporate network (Juniper SSL VPN box).
I’m able to authenticate and connect but after few minutes VPN crash and I have to disconnect and reconnect.
If I’m directly connected to router it is stable. If I’m connected over WiFi I’m experiencing this issue.

Previously I was using low end WiFi router TP-LINK withouth any issues so I think the problem is in MikroTik router.

Please let me know if you have any advice how to solve this issue.

Thank you!

what device?
what version?
what firmware?

what device?
RB951g-2HnD
what version?
OS version v6.26
what firmware?